The present invention relates to high abrasion resistant aluminum bronze alloy, especially aluminum bronze alloy preferable as material for sliding members which slide with sliding portions of mechanical structure steel, and tool steel etc. in various industrial machines such as hydraulic machines and machine tools etc.
Generally speaking, copper alloy has been used as material for sliding members such as, for example, gears, bearings, worm wheels etc. in various industrial machines. Because, if the sliding members are composed from the same material as machine structural steel such as carbon steel, Cr-Mo steel, and case hardening steel etc. or as tool steel such as bearing steel, and high speed steel etc., the abrasion increases by wearing with metal of same kind. Farther, various copper alloys are respectively used depending on characteristics required for each member.
As an example, high tensile brass and aluminum bronze are used for gears and worm wheels which are required for hardness and mechanical strength, and bronze and phosphor bronze are used for bearings which is required for anti-seizing and anti-galling characteristics. Farther, depending on requirement for high strength and high abrasion resistance, Cu-Zn alloy group in which Mn-Si compounds crystallize and are dispersed (JP No. 882216), and Cu-Al alloy group in which Fe-Si compounds crystallize and are dispersed (JP No. 1189793) are proposed. However, the above described alloys are still not sufficient as abrasion resistant alloys, and appearance of farther high performance alloy is expected.
Besides, very hard abrasion resistant aluminum bronze alloy (JP No. 1374020) is proposed as material for cold work dies for active metals such as stainless steel and titanium etc. Because of containing hyper-eutectoid aluminum (more than 12%) and having high Mn composition (Mn: more than 6%), the alloy has small elongation (less than 3% of elongation percentage) as for a mechanical property and is not suitable as sliding members for industrial machines.